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ACI 301-99 supersedes ACI 301-96 and is effective November 3, 1999. Copyright  1999, American Concrete Institute. All rights reserved including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by electronic or mechanical device, printed, written, or oral, or recording for sound or visual reproduc- tion or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors. 301-1 Reported by ACI Committee 301 James A. Lee Chairman W. Calvin McCall Secretary Jon B. Ardahl Mario R. Diaz Gilbert J. Haddad Joseph A. McElroy Domingo J. Carreira Robert M. Eshbach Jerry A. Holland Timothy L. Moore Oleh B. Ciuk W. Bryant Frye Roy H. Keck Jerry Parnes Steven R. Close Richard D. Gaynor Oswin Keifer, Jr. * Aimee Pergalsky D. Gene Daniel Clifford Gordon Ross S. Martin James M. Shilstone, Sr. Marwan A. Daye David P. Gustafson David K. Maxwell * Deceased This Specification is a Reference Specification that the Engineer or Archi- tect can make applicable to any construction project by citing it in the Project Specifications. The Architect/Engineer supplements the provisions of this Reference Specification as needed by designating or specifying indi- vidual project requirements. The document covers materials and proportioning of concrete; reinforc- ing and prestressing steels; production, placing, finishing, and curing of concrete; and formwork design and construction. Methods of treatment of joints and embedded items, repair of surface defects, and finishing of formed and unformed surfaces are specified. Separate sections are devoted to architectural concrete, lightweight concrete, mass concrete, prestressed concrete, and shrinkage-compensating concrete. Provisions governing test- ing, evaluation, and acceptance of concrete as well as acceptance of the structure are included. Keywords: admixtures; aggregates; air entrainment; architectural concrete; buildings; cements; cold-weather construction; compressive strength; con- crete construction; concrete durability; concrete slab; concretes; consolida- tion; conveying; curing; density; evaluation; exposed-aggregate finish; finishes; floors; formwork (construction); grouting; hot-weather construc- tion; inspection; joints (contraction, construction, and isolation); light- weight concrete; materials; mixture proportioning; mixing; placing; prestressed concrete; prestressing steels; reinforced concrete; reinforcing steels; repairs; reshoring; shoring; shrinkage-compensating concrete; speci- fications; subgrades; temperature; tests; tolerances; water-cementitious materials ratio, (w/cm); welded wire fabric. 1.3.2—Cited publications 1.3.3—Field references 1.4—Reference standards and cited publications 1.5—Submittals 1.5.1—General 1.5.2—Testing agency reports 1.6—Quality assurance 1.6.1—General 1.6.2—Testing agencies 1.6.3—Testing responsibilites of Contractor 1.6.4—Testing responsibililites of Owner’s testing agency 1.6.5—Tests on hardened concrete in-place 1.6.6—Evaluation of concrete strength tests 1.6.7—Acceptance of concrete strength 1.6.8—Field acceptance of concrete 1.7—Acceptance of structure 1.7.1—General 1.7.2—Dimensional tolerances 1.7.3—Appearance 1.7.4—Strength of structure 1.7.5—Durability 1.8—Protection of in-place concrete 1.8.1—Loading and support of concrete 1.8.2—Protection from mechanical injury Section 2—Formwork and formwork accessories, p. 301-10 2.1—General 2.1.1—Description 2.1.2—Submittals CONTENTS Foreword, p. 301-3 SPECIFICATION Section 1—General requirements, p. 301-3 1.1—Scope 1.1.1—Work specified 1.1.2—Work not specified 1.2—Definitions 1.3—Standards producing organizations 1.3.1—Reference standards Specifications for Structural Concrete ACI 301-99 301-2 ACI STANDARD 2.2—Products 2.2.1—Materials 2.2.2—Performance and design requirements 2.2.3—Fabrication and manufacture 2.3—Execution 2.3.1—Construction and erection of formwork 2.3.2—Removal of formwork 2.3.3—Reshoring 2.3.4—Strength of concrete required for removal of formwork 2.3.5—Field quality control Section 3—Reinforcement and reinforcement supports, p. 301-13 3.1—General 3.1.1—Submittals, data, and drawings 3.1.2—Materials delivery, storage, and handling 3.2—Products 3.2.1—Materials 3.2.2—Fabrication 3.3—Execution 3.3.1—Preparation 3.3.2—Placement Section 4—Concrete mixtures, p. 301-15 4.1—General 4.1.1—Description 4.1.2—Submittals 4.1.3—Quality control 4.1.4—Materials storage and handling 4.2—Products 4.2.1—Materials 4.2.2—Performance and design requirements 4.2.3—Proportioning 4.3—Execution 4.3.1—Measuring, batching, and mixing 4.3.2—Delivery Section 5—Handling, placing, and constructing, p. 301-20 5.1—General 5.1.1—Description 5.1.2—Submittals 5.1.3—Delivery, storage, and handling 5.2—Products 5.2.1—Materials 5.2.2—Performance and design requirements 5.3—Execution 5.3.1—Preparation 5.3.2—Placement of concrete 5.3.3—Finishing formed surfaces 5.3.4—Finishing unformed surfaces 5.3.5—Sawed contraction joints 5.3.6—Curing and protection 5.3.7—Repair of surface defects Section 6—Architectural concrete, p. 301-26 6.1—General 6.1.1—Description 6.1.2—Submittals 6.1.3—Quality assurance 6.1.4—Product delivery, storage, and handling 6.1.5—Project conditions 6.2—Products 6.2.1—Materials 6.2.2—Performance and design requirements 6.3—Execution 6.3.1—Preparation 6.3.2—Proportioning concrete mixtures 6.3.3—Consolidation 6.3.4—Formwork monitoring 6.3.5—Formwork removal 6.3.6—Repair of tie holes and surface defects 6.3.7—Finishing Section 7—Lightweight concrete, p. 301-27 7.1—General 7.1.1—Description 7.1.2—Submittals 7.2—Products 7.2.1—Aggregates 7.2.2—Performance and design requirements 7.2.3—Mixtures 7.2.4—Batching and mixing 7.3—Execution 7.3.1—Consolidation 7.3.2—Finishing 7.3.3—Field quality control Section 8—Mass concrete, p. 301-28 8.1—General 8.1.1—Description 8.1.2—Submittals 8.2—Products 8.2.1—Materials 8.2.2—Performance and design requirements 8.3—Execution 8.3.1—Placement 8.3.2—Curing and protection Section 9—Prestressed concrete, p. 301-29 9.1—General 9.1.1—Description 9.1.2—Submittals 9.1.3—Quality control 9.1.4—Product delivery, handling, and storage 9.2—Products 9.2.1—Materials 9.2.2—Proportioning of concrete and grout mixtures 9.3—Execution 9.3.1—Inspection 9.3.2—Preparation 9.3.3—Placement 9.3.4—Tensioning and other operations involving tendons Section 10—Shrinkage-compensating concrete, p. 301-32 10.1—General 10.1.1—Scope 301-3SPECIFICATIONS FOR STRUCTURAL CONCRETE 10.1.2—General requirements 10.1.3—Submittals 10.2—Products 10.2.1—Materials 10.2.2—Performance and design requirements 10.2.3—Proportioning 10.2.4—Reinforcement 10.2.5—Isolation-joint filler materials 10.3—Execution 10.3.1—Reinforcement 10.3.2—Placing 10.3.3—Isolation joints 10.3.4—Curing NOTES TO SPECIFIERS Preface to specification checklists, p. 301-33 Flow chart for selection of concrete mixture proportions, p. 301-35 Mandatory requirements checklist, p. 301-36 Notes to Architect/Engineer Optional requirements checklist, p. 301-36 Notes to Architect/Engineer Submittals checklist, p. 301-44 Notes to Architect/Engineer FOREWORD F1. This foreword is included for explanatory purposes only. It does not form a part of Specification ACI 301. F2. Specification ACI 301 is a Reference Specification that the Architect/Engineer may cite in the Project Specifica- tions for any construction project, together with supplemen- tary requirements for the specific project. F3. Each technical section of Specification ACI 301 is written in the Three-Part Section Format of the Construction Specifications Institute, as adapted by ACI and modified to ACI requirements. The language is generally imperative and terse. The Specification is written to the Contractor. When a provision of this specification requires action on the Contrac- tor’s part, the verb “shall” is used. If the Contractor is allowed to exercise an option, the verb “may” or, when limited alter- natives are available, the conjunctive phrase “shall ei- ther or ” is used. Statements provided in the specification as information to the contractor use the verbs “may” or “will.” Informational statements typically identify activities or options that “will” be taken or “may” be taken by the Owner or the Architect/Engineer. F4. Checklists do not form a part of Reference Specifica- tion ACI 301. Checklists are to assist the Architect/Engineer in properly choosing and specifying any necessary require- ments for the Project Specifications. SPECIFICATION SECTION 1—GENERAL REQUIREMENTS 1.1—Scope 1.1.1 Work specified—This Reference Specification cov- ers cast-in-place structural concrete. Provisions of this Specification shall govern except where other provisions are specified in the Contract Documents. 1.1.2 Work not specified—The following subjects are not in the scope of this specification: • Precast concrete products; • Heavyweight shielding concrete; • Slip-formed paving concrete; • Terrazzo; • Insulating concrete; and • Refractory concrete. 1.2—Definitions Acceptable or Accepted—Acceptable to or accepted by the Architect/Engineer. ACI Concrete Field Testing Technician Grade 1—A per- son who has demonstrated knowledge and ability to perform and record the results of ASTM standard tests on freshly mixed concrete and to make and cure test specimens. Such knowledge and ability shall be demonstrated by passing pre- scribed written and performance examinations and having cre- dentials that are current with the American Concrete Institute. Architect/Engineer or Engineer/Architect—The Architect, Engineer, architectural firm, engineering firm, or architec- tural and engineering firm, issuing project drawings and specifications, or administering work under the Contract Documents. Architectural concrete—Concrete that is exposed as an in- terior or exterior surface in the completed structure and is designated as architectural concrete in the Contract Docu- ments; contributes to visual character of the completed struc- ture and therefore requires special care in the selection of the concrete materials, forming, placing, and finishing to obtain the desired architectural appearance. Backshores—Shores placed snugly under a concrete slab or structural member after the original formwork and shores have been removed from a small area without allowing the slab or member to deflect or support its own weight or exist- ing construction loads from above. Cement, expansive— A cement that, when mixed with wa- ter, produces a paste that, after setting, tends to increase in volume to a significantly greater degree than does portland- cement paste; used to compensate for volume decrease due to shrinkage or induce tensile stress in reinforcement. Cement, expansive Type K—A mixture of portland ce- ment, anhydrous tetracalcium trialuminate sulfate (C 4 A 3 S•), calcium sulfate (CaSO 4 ), and lime (CaO); the C 4 A 3 S• is a constituent of a separately burned clinker that is interground with portland cement or alternately, it may be formed simul- taneously with the portland-cement clinker compounds dur- ing the burning process. 301-4 ACI STANDARD Contract Documents—Documents, including the project drawings and Project Specifications, covering the required Work. Contractor— Person, firm, or corporation with whom the Owner enters into an agreement for construction of the Work. Exposed to public view—Situated so that it can be seen from a public location after completion of the building. High-early-strength concrete—Concrete that, through the use of ASTM C 150 Type III cement or admixtures, is capa- ble of attaining specified strength at an earlier age than nor- mal concrete. Lightweight concrete—Concrete of substantially lower density than normalweight concrete. Mass concrete—Any volume of concrete with dimensions large enough to require that measures be taken to cope with generation of heat from hydration of the cement and atten- dant volume change to minimize cracking. Mass concrete, plain—Mass concrete containing no rein- forcement or less reinforcement than necessary to be consid- ered reinforced mass concrete. Mass concrete, reinforced—Mass concrete containing ad- equate reinforcement, prestressed or nonprestressed, de- signed to act together with the concrete in resisting forces including those induced by temperature and shrinkage. Normalweight concrete—Concrete having a density of approximately 150 lb/ft 3 made with gravel or crushed stone aggregates. Owner—Corporation, association, partnership, individual, public body, or authority with whom the Contractor enters into agreement, and for whom the Work is provided. Permitted—Accepted or acceptable to the Architect/Engi- neer usually pertaining to a request by the Contractor, or when specified in the Contract Documents. Post-tensioning—A method of prestressing reinforced concrete in which tendons are tensioned after the concrete has hardened. Prestressed concrete—Concrete where internal stresses of such magnitude and distribution are introduced that the ten- sile stresses resulting from the service loads are counteracted to a desired degree; in reinforced concrete, the prestress is commonly introduced by tensioning the tendons. Project drawings— The drawings that, along with Project Specifications, complete the descriptive information for constructing the Work required or referred to in the Con- tract Documents. Project Specifications— The written documents that specify requirements for a project in accordance with the service param- eters and other specific criteria established by the Owner. Reference specification—A specification that is intended by the Architect/Engineer to be a reference standard for the Contractor to use in the construction of a project by citing the reference specification in the Contract Documents, together with the project requirements. Reference standards— Standards of a technical society, or- ganization, or association, including the codes of local or state authorities, that are referenced in the Contract Documents. Required—Required in this Reference Specification or the Contract Documents. Reshores—Shores placed snugly under a stripped con- crete slab or other structural member after the original forms and shores have been removed from a large area, thus requir- ing the new slab or structural member to deflect and support its own weight and existing construction loads applied be- fore the installation of the reshores. Shrinkage-compensating concrete—A concrete made us- ing an expansive cement in which volume increases after set- ting, if properly elastically restrained, induce compressive stresses that are intended to approximately offset the tenden- cy of drying shrinkage to induce tensile stresses. Strength test—The average of the compressive strengths of two cylinders made from the same sample of concrete and tested at 28 days or at test age designated for determination of specified compressive strength f c ′. Structural lightweight concrete—Structural concrete made with lightweight aggregate; the density usually is in the range of 90 to 115 lb/ft 3 . Submitted—Submitted to the Architect/Engineer for re- view and acceptance. Work—The entire construction or separately identifiable parts thereof that are required to be furnished under the Con- tract Documents; work is the result of performing services, furnishing labor, and furnishing and incorporating materials and equipment into the construction in accordance with the Contract Documents. 1.3—Reference standards and cited publications 1.3.1 Reference standards—Standards of ACI, ASTM, CRD, PTI, and AWS referred to in this Reference Specifica- tion are listed with serial designation including year of adop- tion or revision and are part of this Reference Specification. 1.3.1.1 ACI standards ACI 117-90 Specifications for Tolerances for Concrete Construction and Materials 1.3.1.2 ASTM standards A 82-97a Standard Specification for Steel Wire, Plain, for Concrete Reinforcement A 184/ Standard Specification for Fabricated De- A 184M-96 formed Steel Bar Mats for Concrete Rein- forcement A 185-97 Standard Specification for Steel Welded Wire Fabric, Plain, for Concrete Reinforcement A 416/ Standard Specification for Steel Strand, A 416M-98 ε 1 Uncoated Seven-Wire, for Prestressed Concrete A 421/ Standard Specification for Uncoated Stress- A 421M-98a Relieved Steel Wire for Prestressed Concrete A 496-97a Standard Specification for Steel Wire, Deformed, for Concrete Reinforcement A 497-97 Standard Specification for Steel Welded Wire Fabric, Deformed, for Concrete Reinforcement A 615/ Standard Specification for Deformed and Plain A 615M-96a Billet-Steel Bars for Concrete Reinforcement A 616/ Standard Specification for Rail-Steel Deformed A 616M-96a and Plain Bars for Concrete Reinforcement 301-5SPECIFICATIONS FOR STRUCTURAL CONCRETE A 617/ Standard Specification for Axle-Steel Deformed A 617M-96a and Plain Bars for Concrete Reinforcement A 706/ Standard Specification for Low-Alloy Steel A 706M-98 ε 1 Deformed and Plain Bars for Concrete Reinforcement A 722/ Standard Specification for Uncoated High- A 722M-98 Strength Steel Bars for Prestressing Concrete A 767/ Standard Specification for Zinc-Coated A 767M-97 ( Galvanized) Steel Bars for Concrete Reinforcement A 775/ Standard Specification for Epoxy-Coated A 775M-97 ε 1 Reinforcing Steel Bars A 779/ Standard Specification for Steel Strand, Seven- A 779M-98 Wire, Uncoated, Compacted, Stress-Relieved for Prestressed Concrete A 780-93a Standard Practice for Repair of Damaged Hot-Dip Galvanized Coatings A 884/ Standard Specification for Epoxy-Coated Steel A 884M-96a ε 1 Wire and Welded Wire Fabric for Reinforcement A 934/ Standard Specification for Epoxy-Coated A 934M-97 ε 1 Prefabricated Steel Reinforcing Bars A 955M-96 Standard Specification for Deformed and Plain Stainless Steel Bars for Concrete Reinforcement A 970/ Standard Specification for Welded or Forged A 970M-98 Headed Bars for Concrete Reinforcement A 996/ Standard Specification for Rail-Steel and A 996M-98 Axle-Steel Deformed Bars for Concrete Reinforcement C 31/ Standard Practice for Making and Curing C 31M-98 Concrete Test Specimens in the Field C 33-99 Standard Specification for Concrete Aggregates C 39/ Standard Test Method for Compressive C 39M-99 Strength of Cylindrical Concrete Specimens C 42/ Standard Test Method for Obtaining and C 42M-99 Testing Drilled Cores and Sawed Beams of Concrete C 94/C 94M-99 Standard Specification for Ready-Mixed Concrete C 138-92 Standard Test Method for Unit Weight, Yield, and Air Content (Gravimetric) of Concrete C 143/ Standard Test Method for Slump of Hydraulic- C 143M-98 Cement Concrete C 150-99 Standard Specification for Portland Cement C 171-97a Standard Specification for Sheet Materials for Curing Concrete C 172-97 Standard Practice for Sampling Freshly Mixed Concrete C 173-94a ε 1 Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method C 192/ Standard Practice for Making and Curing C 192M-98 Concrete Test Specimens in the Laboratory C 231-97 ε 1 Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method C 260-98 Standard Specification for Air-Entraining Admixtures for Concrete C 309-98a Standard Specification for Liquid Membrane- Forming Compounds for Curing Concrete C 330-99 Standard Specification for Lightweight Aggregates for Structural Concrete C 387-99 Standard Specification for Packaged, Dry, Combined Materials for Mortar and Concrete C 404-97 Standard Specification for Aggregates for Masonry Grout C 494-99 Standard Specification for Chemical Admixtures for Concrete C 567-99a Standard Test Method for Density of Structural Lightweight Concrete C 595-98 Standard Specification for Blended Hydraulic Cements C 597-97 Standard Test Method for Pulse Velocity Through Concrete C 618-99 Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete C 684-96 Standard Test Method for Making, Accelerated Curing, and Testing Concrete Compression Test Specimens C 685-98a Standard Specification for Concrete Made By Volumetric Batching and Continuous Mixing C 803/ Standard Test Method for Penetration Resistance C 803M-97 of Hardened Concrete C 805-97 Standard Test Method for Rebound Number of Hardened Concrete C 845-96 Standard Specification for Expansive Hyd raulic Cement C 873-99 Standard Test Method for Compressive Strength of Concrete Cylinders Cast in Place in Cylindrical Molds C 878-95a Standard Test Method for Restrained Expansion of Shrinkage-Compensating Concrete C 881-99 Standard Specification for Epoxy-Resin-Base Bonding Systems for Concrete C 900-99 Standard Test Method for Pullout Strength of Hardened Concrete C 928-99 Standard Specification for Packaged, Dry, Rapid Hardening Cementitious Materials for Concrete Repairs C 989-99 Standard Specification for Ground Granulated Blast-Furnace Slag for Use in Concrete and Mortars C 1017/ Standard Specification for Chemical Admixtures C 1017M-98 for Use in Producing Flowing Concrete C 1059-99 Standard Specification for Latex Agents for Bonding Fresh to Hardened Concrete C 1064/ Standard Test Methods for Temperature of C 1064M-99 Freshly Mixed Portland Cement Concrete C 1074-98 Standard Practice for Estimating Concrete Strength by the Maturity Method C 1077-99 Standard Practice for Laboratories Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Laboratory Evaluation C 1107-99 Standard Specification for Packaged Dry, Hydraulic Cement Grout (Nonshrink) 301-6 ACI STANDARD C 1150-96 Standard Test Method for the Break-Off Number of Concrete C 1218/ Standard Test Method for Water-Soluble C 1218M-99 Chloride in Mortar and Concrete C 1240-99 Standard Specification for Silica Fume for Use in Hydraulic-Cement Concrete, Mortar, and Grout C 1315-95 Standard Specification for Liquid Membrane- Forming Compounds Having Special Properties for Curing and Sealing Concrete D 98-95 Standard Specification for Calcium Chloride D 994-98 Standard Specification for Preformed Expansion Joint Filler for Concrete (Bituminous Type) D 1621-94 Standard Test Methods for Compressive Properties of Rigid Cellular Plastics D 1751-99 Standard Specification for Preformed Expansion Joint Fillers for Concrete Paving and Structural Construction (Non-extruding and Resilient Bituminous Types) D 1752-84 Standard Specification for Preformed Sponge (1996) e1 Rubber and Cork Expansion Joint Fillers for Concrete Paving and Structural Construction D 3575-93 Standard Test Methods for Flexible Cellular Materials Made from Olefin Polymers E 329-98a Standard Specification for Agencies Engaged in the Testing and/or Inspection of Materials Used in Construction E 1155-96 Standard Test Method for Determining Floor Flatness and Levelness Using the F-Number System 1.3.1.3 Other referenced standards—Other standards referenced in this Reference Specification: ANSI/ Structural Welding Code—Reinforcing AWS D-1.4-98 Steel CRD-C 513-74 Specification for Rubber Waterstops CRD-C 572-74 Specification for Polyvinylchloride Waterstops PTI 1993 Specification for Unbonded Single Strand Tendons 1.3.2 Cited publications—Publications cited in this Refer- ence Specification: ACI 318-99 Building Code Requirements for Reinforced Concrete ACI CP1-98 ACI Certification Concrete Field Testing Technician—Grade I ACI SP-15 Field Reference Manual CRSI MSP-1-97 Manual of Standard Practice, 26th Edition 1.3.3 Field references—Keep in Contractor’s field office a copy of the following reference: SP-15 Field Reference Manual: Specification for Structural Concrete (ACI 301-99) with Selected ACI and ASTM References. 1.4—Standards-producing organizations Abbreviations for and complete names and addresses of organizations issuing documents referred to in this Reference Specification are listed: American Concrete Institute (ACI) P.O. Box 9094 Farmington Hills, MI 48333-9094 American Society for Testing and Materials (ASTM) 100 Barr Harbor Drive West Conshohocken, PA 19428 American Welding Society (AWS) 550 N.W. Le Jeune Road P.O. Box 351040 Miami, FL 33135 Concrete Plant Manufacturers Bureau (CPMB) 900 Spring Street Silver Spring, MD 20910 Concrete Reinforcing Steel Institute (CRSI) 933 N. Plum Grove Road Schaumburg, IL 60173 U.S. Army Corps of Engineers [COE(CRD)] Waterways Experiment Station 3909 Halls Ferry Road Vicksburg, MS 39180 National Ready Mixed Concrete Association (NRMCA) 900 Spring Street Silver Spring, MD 20910 Post Tensioning Institute (PTI) 1717 W. Northern Avenue #218 Phoenix, AZ 85021 1.5—Submittals 1.5.1 General—Unless otherwise specified, submittals re- quired in this Reference Specification shall be submitted for review and acceptance. 1.5.2 Testing agency reports—Testing agencies shall re- port results of concrete and concrete materials tests and in- spections performed during the course of the Work to the Owner, Architect/Engineer, Contractor, and the concrete supplier. Strength test reports shall include location in the Work where the batch represented by test was deposited and the batch ticket number. Reports of strength tests shall in- clude detailed information of storage and curing of speci- mens before testing. Final reports shall be provided within 7 days of test completion. 1.6—Quality assurance 1.6.1 General—Concrete materials and operations may be tested and inspected by the Owner as work progresses. Fail- ure to detect defective work or material early will not prevent rejection if a defect is discovered later nor shall it obligate the Architect/Engineer for final acceptance. 1.6.2 Testing agencies— Agencies that perform testing ser- vices on concrete materials shall meet the requirements of ASTM C 1077. Testing agencies that perform testing services 301-7SPECIFICATIONS FOR STRUCTURAL CONCRETE on reinforcing steel shall meet the requirements of ASTM E 329. Testing agencies performing the testing shall be ac- cepted by the Architect/Engineer before performing any work. Field tests of concrete required in 1.6.3 and 1.6.4 shall be made by an ACI Concrete Field Testing Technician Grade 1 in accordance with ACI CP1 or equivalent. Equivalent certifi- cation programs shall include requirements for written and per- formance examinations as stipulated in ACI publication CP1. 1.6.3 Testing responsibilities of Contractor 1.6.3.1 Submit data on qualifications of proposed testing agency for acceptance. Use of testing services will not relieve the Contractor of the responsibility to furnish materials and construction in full compliance with the Contract Documents. 1.6.3.2 Duties and responsibilities—Unless otherwise specified in the Contract Documents, the Contractor shall assume the following duties and responsibilities: 1.6.3.2.a Qualify proposed materials and establish mixture proportions. 1.6.3.2.b Furnish any necessary labor to assist Owner’s testing agency in obtaining and handling samples at the project site or at the source of materials. 1.6.3.2.c Advise Owner’s testing agency at least 24 hr in advance of operations to allow for completion of quality tests and for assignment of personnel. 1.6.3.2.d Provide and maintain for the sole use of the testing agency adequate facilities for safe storage and proper curing of concrete test specimens on the project site for ini- tial curing as required by ASTM C 31/C 31M. 1.6.3.2.e Submit data and test documentation on ma- terials and mixture proportions. 1.6.3.2.f Submit quality-control program of the con- crete supplier and provide copies of test reports pertaining to the work. 1.6.3.2.g When specified or permitted to base con- crete acceptance on accelerated strength testing, submit cor- relation data for the standard 28-day compressive strength based on at least 15 sets of test data in accordance with 1.6.4.2.d with concrete made with the same materials provid- ing a range of at least the required average strength f cr ′ , plus or minus 1000 ps i. 1.6.3.3 Tests required of Contractor’s testing agency— Unless otherwise specified in the Contract Documents, the Contractor shall provide at no cost to the Owner the neces- sary testing services for the following: 1.6.3.3.a Qualification of proposed materials and es- tablishment of concrete mixtures. 1.6.3.3.b Other testing services needed or required by Contractor. 1.6.4 Testing responsibilities of Owner’s testing agency 1.6.4.1 Unless otherwise specified in the Contract Doc- uments, the Owner’s testing agency will provide the neces- sary services for the following: 1.6.4.1.a Representatives of the Owner’s testing agen- cy will inspect, sample, and test materials and production of concrete required by the Architect/Engineer. When it appears that material furnished or work performed by the Contractor fails to conform to Contract Documents, the testing agency will immediately report such deficiency to the Architect/En- gineer, Contractor, and concrete supplier. 1.6.4.1.b The testing agency and its representatives are not authorized to revoke, alter, relax, enlarge, or release any requirement of the Contract Documents, nor to accept any portion of the Work. 1.6.4.1.c The testing agency will report test and in- spection results that pertain to the Work to the Architect/En- gineer, Contractor, and concrete supplier within 7 days after tests and inspections are performed. 1.6.4.2 Testing services— When required by the Owner or the Architect/Engineer, the Owner’s testing agency will per- form the following testing services at no cost to the Contractor: 1.6.4.2.a Review and check-test proposed materials for compliance with Contract Documents. 1.6.4.2.b Review and check-test proposed concrete mixture as required by the Architect/Engineer. 1.6.4.2.c Obtain production samples of materials at plants or stockpiles during the course of the Work and test for compliance with the Contract Documents. 1.6.4.2.d Obtain samples in accordance with ASTM C 172. Select the trucks or batches of concrete to be tested on a random basis, using random numbers selected before com- mencement of concrete placement. Obtain at least one composite sample for each 100 yd 3 , or frac- tion thereof, of each concrete mixture placed in any one day. When the total quantity of a given concrete mixture is less than 50 yd 3 , the strength tests may be waived by the Archi- tect/Engineer. 1.6.4.2.e Conduct strength tests of concrete during construction in accordance with the following procedures: • Mold and cure three cylinders from each sample in accordance with ASTM C 31/C 31M. Record any devi- ations from the ASTM requirements in the test report. • Test cylinders in accordance with ASTM C 39. Test one specimen at 7 days for information, and two specimens at 28 days for acceptance, unless otherwise specified. The compressive strength test results for acceptance shall be the average of the compressive strengths from the two specimens tested at 28 days. If one specimen in a test shows evidence of improper sampling, molding, or testing, discard the specimen and consider the strength of the remaining cylinder to be the test result. If both specimens in a test show any defects, discard the entire test. • When accelerated testing of concrete is specified or per- mitted as an alternative to standard testing, mold and cure two specimens from each composite sample in accordance with ASTM C 684, following the procedure specified by the Architect/Engineer. Make at least one accelerated strength test from each composite sample in 1.6.4.2.d and one standard 28-day compressive-strength test for at least every other accelerated strength test in accordance with ASTM C 31/C 31M. Use these test results to maintain and update the correlation between accelerated and standard 28-day compressive-strength tests. 301-8 ACI STANDARD 1.6.4.2.f Determine slump of each composite sample taken in accordance with 1.6.4.2.d and whenever consistency of concrete appears to vary, using ASTM C 143/C 143M. 1.6.4.2.g Determine the temperature of each composite sample taken in accordance with 1.6.4.2.d using ASTM C 1064. 1.6.4.2.h Determine the air content of normalweight concrete using ASTM C 231, C 173, or C 138 for each com- posite sample taken in accordance with 1.6.4.2.d or as direct- ed by the Architect/Engineer. Additional tests will be performed as necessary. 1.6.4.2.i Where concrete will be exposed to deicing salts as indicated in the Contract Documents, air content tests will be made on samples from the first three batches in the placement and until three consecutive batches have air con- tents within the range specified in 4.2.2.4—Air content, at which time every fifth batch will be tested. This test frequen- cy will be maintained until a batch is not within the range specified in 4.2.2.4, at which time testing of each batch will be resumed until three consecutive batches have air contents within the range specified in 4.2.2.4. Additional tests may be performed as necessary for control. These air content tests may be taken on composite samples in 1.6.4.2.d or on samples from the batch at any time after discharge of 2 ft 3 of concrete. 1.6.4.3 Additional testing services when required—The Owner’s testing agency will perform the following testing services when required by the Architect/Engineer, at no cost to the Contractor: • Inspect concrete batching, mixing, and delivery operations; • Inspect forms, foundation preparation, reinforcing steel, embedded items, reinforcing steel placing, and concrete placing, finishing, and curing operations; • Sample concrete at point of placement and other loca- tions as directed by the Architect/Engineer and perform required tests; • Review the manufacturer’s report for each shipment of cement, reinforcing steel, and prestressing tendons, and conduct laboratory tests or spot checks of the materials received for compliance with specifications; and • Other testing or inspection services as required by the Architect/Engineer. 1.6.4.4 Other testing services as needed—The contrac- tor shall pay for the following testing services performed, when necessary, by the Owner’s testing agency: • Additional testing and inspection required because of changes in materials or mixture proportions requested by the Contractor; and • Additional testing of materials or concrete occasioned by failure to meet specification requirements. 1.6.5 Tests on hardened concrete in-place 1.6.5.1 General—Tests on hardened concrete will be performed by the Owner’s testing agency when such tests are needed. Testing shall be at the Contractor’s expense when tests are performed to verify the strength of the structure when re- quired by this specification. The Owner will pay costs if tests are at the Owner’s request and not required by this Specification. 1.6.5.2 Nondestructive tests—Use of the rebound ham- mer in accordance with ASTM C 805, pulse-velocity method in accordance with ASTM C 597, or other nondestructive tests may be permitted by the Architect/Engineer in evaluat- ing the uniformity and relative concrete strength in-place, or for selecting areas to be cored. 1.6.5.3 Core tests 1.6.5.3.a Where required by the Architect/Engineer, c ores shall be obtained and tested in accordance with ASTM C 42. If concrete in the structure will be dry under service con- ditions, the cores shall be air dried [temperature 60 to 80 F , relative humidity less than 60%] for 7 days before testing and shall be tested dry. If concrete in the structure will be more than superficially wet under service conditions, the core shall be tested after moisture conditioning in accordance with ASTM C 42. 1.6.5.3.b At least three representative cores shall be taken from each member or area of concrete in place that is considered potentially deficient. The location of cores as de- termined by the Architect/Engineer shall impair the strength of the structure as little as possible. If, before testing, cores show evidence of having been damaged subsequent to or during removal from the structure, replacement cores shall be taken. 1.6.5.3.c Fill core holes with low-slump concrete or mortar of a strength equal to or greater than the original concrete. 1.6.6 Evaluation of concrete strength tests 1.6.6.1 Standard molded and cured strength speci- mens—Test results from standard molded and cured test cyl- inders shall be evaluated separately for each specified concrete mixture. Evaluation will be valid only if tests have been conducted in accordance with procedures specified. For evaluation, each specified mixture shall be represented by at least five tests. 1.6.6.2 Nondestructive tests—Test results will be eval- uated by the Architect/Engineer and will be valid only if tests have been conducted using properly calibrated equip- ment in accordance with recognized standard procedures and an acceptable correlation between test results and con- crete compressive strength has been established and is sub- mitted. 1.6.6.3 Core tests—Core test results will be evaluated by the Architect/Engineer and will be valid only if tests have been conducted in accordance with specified procedures. 1.6.7 Acceptance of concrete strength 1.6.7.1 Standard molded and cured strength speci- mens—The strength level of concrete will be considered sat- isfactory when the averages of all sets of three consecutive compressive strength test results equal or exceed the speci- fied compressive strength f c ′, and no individual strength test result falls below the specified compressive strength f c ′ by more than 500 psi. These criteria apply also when accelerat- ed strength testing is specified unless another basis for ac- ceptance is specified in the Contract Documents. 1.6.7.2 Nondestructive tests— Nondestructive tests shall not be used as the sole basis for accepting or rejecting con- crete, but may be used when permitted to evaluate concrete 301-9SPECIFICATIONS FOR STRUCTURAL CONCRETE where standard molded and cured cylinders have yielded re- sults not meeting the criteria in 1.6.7.1. 1.6.7.3 Core tests—Strength level of concrete in the area represented by core tests will be considered adequate when the average compressive strength of the cores are equal to at least 85% of specified compressive strength f c ′, and if no single core is less than 75% of the specified com- pressive strength f c ′. 1.6.8 Field acceptance of concrete 1.6.8.1 Air content—Concrete not within the limits of air-entrainment indicated in 4.2.2.4 and tested in accordance with 1.6.4.2.h shall not be used in the Work. 1.6.8.2 Slump— Concrete not within the slump limits of 4.2.2.2 at the point of placement shall not be used in the Work. 1.6.8.3 Temperature—Concrete not within temperature limits of 4.2.2.7 shall not be used in the Work. 1.7—Acceptance of structure 1.7.1 General—Completed concrete work shall conform to applicable requirements of this Reference Specification and the Contract Documents. 1.7.1.1 C oncrete work that fails to meet one or more re- quirements of the Contract Documents but subsequently is re- paired to bring the concrete into compliance may be accepted. 1.7.1.2 Concrete work that fails to meet one or more re- quirements of the Contract Documents and cannot be brought into compliance may be rejected. 1.7.1.3 Repair rejected concrete work by removing and replacing or by reinforcing with additional construction re- quired by the Architect/Engineer. To bring rejected work into compliance, use repair methods that will maintain spec- ified strength and meet applicable requirements for function, durability, dimensional tolerances, and appearance as deter- mined by the Architect/Engineer. 1.7.1.4 Submit for acceptance the proposed repair meth- ods, materials, and modifications needed to assure that con- crete work will meet requirements of Contract Documents. 1.7.1.5 Contractor shall pay all costs to bring concrete work into compliance with requirements of Project Specifi- cation. 1.7.1.6 Concrete members cast in the wrong location may be rejected. 1.7.2 Dimensional tolerances 1.7.2.1 Formed surfaces resulting in concrete outlines smaller than permitted by the tolerances of ACI 117, may be considered deficient in strength and subject to the provisions of 1.7.4—Strength of structure. 1.7.2.2 Formed surfaces resulting in concrete outlines larger than permitted by ACI 117 may be rejected. Remove excess materials when required by the Architect/Engineer. 1.7.2.3 Inaccurately formed concrete surfaces that ex- ceed ACI 117 tolerances may be rejected. 1.7.2.4 Finished slabs exceeding the tolerances in 5.3.4.3—Finishing tolerances for slabs, may be corrected provided strength or appearance are not adversely affected. 1.7.2.5 Concrete with tolerances and defects exceeding the limitations of 2.2.2.4 may be rejected. 1.7.3 Appearance 1.7.3.1 Concrete not meeting the requirements of 5.3.3— Finishing formed surfaces, or 5.3.4— Finishing un- formed surfaces shall be brought into compliance in accor- dance with 1.7.1—General. 1.7.4 Strength of structure 1.7.4.1 Criteria for determining potential strength defi- ciency—Strength will be considered deficient and concrete work will be rejected when the work fails to comply with re- quirements that control the strength of the structure includ- ing, but not limited to, the following conditions: 1.7.4.1.a Concrete strength failing to comply with re- quirements of 1.6.7—Acceptance of concrete strength. 1.7.4.1.b Reinforcing steel size, quantity, strength, position, or arrangement at variance with the requirements of Section 3—Reinforcement and reinforcement supports, or other Contract Documents. 1.7.4.1.c Concrete elements that differ from the re- quired dimensions or location. 1.7.4.1.d Curing not in accordance with Contract Documents. 1.7.4.1.e Inadequate protection of concrete from ex- treme temperature and other environmental conditions dur- ing early stages of hardening and strength development. 1.7.4.1.f Mechanical injury, construction fires, acci- dents, or premature removal of formwork resulting in defi- cient strength. 1.7.4.2 Action required when strength is potentially de- ficient—When strength of the structure is considered poten- tially deficient, the following actions may be required by the Architect/Engineer: 1.7.4.2.a Structural analysis or additional testing, or both. 1.7.4.2.b Core tests. 1.7.4.2.c If testing is inconclusive or impractical or if structural analysis does not confirm the safety of the struc- ture, load tests may be required and their results evaluated in accordance with ACI 318. 1.7.4.2.d Concrete work rejected by structural analysis or by results of a load test shall be strengthened with addi- tional construction when required by the Architect/Engineer, or replaced. 1.7.4.2.e Document all repair work proposed to bring strength-deficient concrete work into compliance with Con- tract Documents, and submit the documentation to the Archi- tect/Engineer for acceptance. 1.7.5 Durability 1.7.5.1 Criteria for determining potential durability de- ficiency— Durability of concrete work will be considered deficient and the concrete work will be rejected when it fails to comply with the requirements that control durabil- ity of the structure including, but not limited to, the fol- lowing conditions: 1.7.5.1.a—Strength failing to comply with 1.6.7—Ac- ceptance of concrete strength. 1.7.5.1.b—Materials for concrete not conforming with the requirements in 4.2.1.1—Cements, 4.2.1.2—Aggregates, 301-10 ACI STANDARD 4.2.1.3—Water, and 4.2.1.4—Admixtures, including air-en- trainment. 1.7.5.1.c—Concrete not conforming with the air-en- trainment requirements in Contract Documents or the air content limits of Table 4.2.2.4. 1.7.5.1.d—Curing not in accordance with Contract Documents. 1.7.5.1.e—Inadequate protection of concrete from temperature and other environmental conditions during early stages of hardening and strength development. 1.7.5.1.f —Concrete not conforming to the maximum allowable chloride-ion content requirements in Table 4.2.2.6. 1.7.5.2 Action required when durability is potentially deficient—When durability of the structure is considered to be deficient, the following actions may be required by the Architect/Engineer: 1.7.5.2.a—Obtain and test samples of the ingredient materials used in the concrete. 1.7.5.2.b—Obtain samples of concrete from the struc- ture by coring, sawing, or other acceptable means. 1.7.5.2.c—Laboratory evaluation of concrete and con- crete materials to assess the ability of concrete to resist weathering action, chemical attack, abrasion, reinforcement corrosion, or other deterioration. 1.7.5.2.d—Repair or replace concrete rejected for lack of durability as directed by the Architect/Engineer. 1.7.5.2.e—Document repair work to bring concrete work into compliance with Contract Documents and submit the documentation to the Architect/Engineer for acceptance. 1.8—Protection of in-place concrete 1.8.1 Loading and support of concrete—Do not allow con- struction loads to exceed the superimposed load that the structural member, with necessary supplemental support, is capable of carrying safely and without damage. 1.8.2 Protection from mechanical injury—During the cur- ing period, protect concrete from damaging mechanical dis- turbances including load stresses, shock, and harmful vibration. Protect concrete surfaces from damage by con- struction traffic, equipment, materials, rain or running water, and other adverse weather conditions. SECTION 2—FORMWORK AND FORMWORK ACCESSORIES 2.1—General 2.1.1 Description—This section covers design, construc- tion, and treatment of formwork to confine and shape con- crete to the required dimensions. 2.1.2 Submittals 2.1.2.1 Submit the following data unless otherwise specified: a. Formwork facing materials—Data on form-facing mate- rials proposed for smooth-form finish if different from that specified in 2.2.1.1—Form-facing materials. b. Construction and contraction joints—Location of con- struction and contraction joints proposed if different from those indicated in the Contract Documents. c. Testing for formwork removal—Data on method for de- termining strength of concrete for removal of formwork in accordance with 2.3.4.2 when a method other than field- cured cylinders is proposed. d. Formwork removal plans—Detail plans for formwork removal operations when removal of forms at concrete strengths lower than that specified in 2.3.2.5 is proposed. e. Reshoring and backshoring plans—When reshoring or backshoring is required or permitted, submit procedures and plans of operations, before use, sealed by a professional En- gineer licensed in the state where work will be performed. f. Data on formwork release agent or form liner proposed for use with each formed surface. 2.1.2.2 Submit the following when required by the Con- tract Documents: a. Shop drawings for formwork sealed by a professional Engineer licensed in the state where the work will be done. b. Calculations for formwork, reshoring and backshoring, sealed by a professional Engineer licensed in the state where the work will be done. c. Manufacturer’s data and samples of form ties. d. Manufacturer’s data and samples of expansion joint ma- terials. e. Manufacturer’s data and samples of waterstops. 2.2—Products 2.2.1 Materials 2.2.1.1 Form-facing materials—Materials for form fac- es in contact with concrete shall meet 5.3.3.5—Unspecified finishes, and the following requirements unless otherwise specified in Contract Documents. • For rough form finish—No form-facing material is specified. • For smooth form finish—Use plywood, tempered con- crete-form-grade hardboard, metal, plastic, paper, or other acceptable materials capable of producing the desired finish for form-facing materials. Form-facing materials shall produce a smooth, uniform texture on the concrete. Do not use form-facing materials with raised grain, torn surfaces, worn edges, patches, dents, or other defects that will impair the texture of concrete surfaces. 2.2.1.2 Formwork accessories—Use commercially manufactured accessories for formwork accessories that are partially or wholly embedded in concrete, including ties and hangers. Do not use nonfabricated wire form ties. Where in- dicated in the Contract Documents, use form ties with inte- gral water barrier plates in walls. 2.2.1.3 Formwork release agents—Use commercially manufactured formwork release agents that will prevent formwork absorption of moisture, prevent bond with con- crete, and not stain the concrete surfaces. 2.2.1.4 Expansion joint filler—Premolded expansion joint filler shall conform to ASTM D 994, D 1751, or D 1752. 2.2.1.5 Other embedded items—Use waterstops, sleeves, inserts, anchors, and other embedded items of the material and design indicated in the Contract Documents. Waterstop materials shall meet requirements of CRD C 513 for rubber waterstop, or CRD C 572 for polyvinylchloride [...]... Specification for Cold Weather Concreting ACI 308 Standard Practice for Curing Concrete ACI 311.1R ACI Manual of Concrete Inspection (SP-2) ACI 311.4R Guide for Concrete Inspection ACI 311.5R Guide for Specifying Batch Plant Inspection and Field Testing of ReadyMixed Concrete ACI 318R Commentary to Building Code Requirements for Structural Concrete ACI 347R Guide to Formwork for Concrete ACI CP 10 Concrete. .. before placing reinforcing steel Do not allow formwork release agent to puddle in the forms Do not allow formwork release agent to contact reinforcing steel or hardened concrete against which fresh concrete is to be placed 2.3.2 Removal of formwork 2.3.2.1 When finishing is required, remove forms as soon as removal operations will not damage concrete 2.3.2.2 Remove top forms on sloping surfaces of concrete. .. American Concrete Institute (ACI) ACI 117R Commentary on Standard Specifications for 301-35 Tolerances for Concrete Construction and Materials ACI 201.2R Guide to Durable Concrete ACI 207.2R Effect of Restraint, Volume Change, and Reinforcement on Cracking of Mass Concrete ACI 211.1 Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass Concrete ACI 222R Corrosion of Metals in Concrete. .. permitted, do not extend welded wire fabric through contraction joints Support welded wire fabric during placing of concrete to ensure required position- SPECIFICATIONS FOR STRUCTURAL CONCRETE Table 3.3.2.3—Minimum concrete cover for reinforcement Minimum concrete cover for reinforcement, except for extremely corrosive atmospheres, other severe exposures, or fire protection, shall be as follows: Minimum... Reinforcement supports—Unless otherwise permitted, use the following reinforcement supports: 3.3.2.4.a Place reinforcement supported from the ground or mud mat on precast concrete reinforcement supports 3.3.2.4.b Place noncoated reinforcement supported from formwork on reinforcement supports made of concrete, metal, or plastic 3.3.2.4.c Place zinc-coated (galvanized) reinforcement supported from formwork... forms and before concrete placement 2.3.1.7 Anchor formwork to shores, supporting surfaces, or members to prevent upward or lateral movement of the formwork system during concrete placement 2.3.1.8 Construct formwork for wall openings to facilitate removal and to counteract swelling of wood formwork 2.3.1.9 Provide runways for moving equipment and support runways directly on the formwork or structural. .. requirements except as specified in ACI 117 3.3.2.2 Reinforcement relocation—When necessary to move reinforcement beyond the specified placing tolerances to avoid interference with other reinforcement, conduits, or embedded items, submit the resulting arrangement of reinforcement for acceptance 3.3.2.3 Concrete cover—Minimum concrete cover for reinforcement, except for extremely corrosive atmosphere, other severe... struts Do not make adjustments in the formwork after concrete has reached its time of initial setting Brace formwork securely against lateral deflection and lateral instability 2.3.1.4 To maintain specified tolerances, camber formwork to compensate for anticipated deflections in formwork before hardening of concrete Set formwork and intermediate screed strips for slabs accurately to produce designated... allow concrete to sag Perform needed repairs or treatment required at once and follow immediately with specified curing 2.3.2.3 Loosen wood formwork for wall openings when this can be accomplished without causing damage to the concrete 2.3.2.4 Do not allow removal of formwork for columns, walls, sides of beams, and other parts not supporting the weight of the concrete to damage the concrete Perform... 5.5 4 3/4 1 6 6 5 4.5 3.5 3 1-1/2 the concrete shall be submitted for acceptance before use in concrete 4.2.2 Performance and design requirements 4.2.2.1 Cementitious-materials content—The cementitious-materials content shall be adequate for concrete to satisfy the specified requirements for strength, watercementitious materials ratio, and finishing ability For concrete used in floors, cementitious-materials . for Steel Wire, Deformed, for Concrete Reinforcement A 497-97 Standard Specification for Steel Welded Wire Fabric, Deformed, for Concrete Reinforcement A 615/ Standard Specification for Deformed. 615M-96a Billet-Steel Bars for Concrete Reinforcement A 616/ Standard Specification for Rail-Steel Deformed A 616M-96a and Plain Bars for Concrete Reinforcement 301- 5SPECIFICATIONS FOR STRUCTURAL CONCRETE A. Specification for Axle-Steel Deformed A 617M-96a and Plain Bars for Concrete Reinforcement A 706/ Standard Specification for Low-Alloy Steel A 706M-98 ε 1 Deformed and Plain Bars for Concrete Reinforcement A

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